Citrus juice extraction on a commercial scale can be advantageously performed with a juice extractor including upper and lower cups that move relative to one another along a reciprocal path of travel. The sides of both the upper and lower cups typically comprise fingers that support a fruit so that it can be squeezed without bursting. The fingers of the upper cup interdigitate or intermesh with those of the lower cup.
An orange or other fruit can be fed, for example, to the bottom cup by a cam-operated feeding device. The upper and lower cups are then brought together so that the respective fingers of the cup intermesh and the fruit therebetween is accordingly squeezed. Sharp, typically circular, cutters are positioned in the top and bottom cups. As the cups move relative to one another, the fruit is pressed against the cutters. The cutters cut plugs from both the top and bottom portions of the fruit as the interdigitating fingers of the two cups mesh together.
The cutting of the plug from the top portion of the fruit promotes separation of the peel from the internal portions of the fruit (i.e., juice and pulp). The plug cut from the lower portion of the fruit allows the internal portions of the fruit to be forced down into a strainer tube positioned just below the lower cup cutter. The strainer tube, in turn, is positioned within a manifold.
Such whole fruit juice extraction is disclosed in commonly assigned U.S. Pat. Nos. 5,970,861; 5,992,311; 5,996,485; and 6,568,319 the entire disclosures of which are incorporated herein by reference. Additional enhancements in this type of fruit juice extraction technology are disclosed in commonly assigned U.S. Pat. Publication No. 2006/0037498, for example, the disclosure of which is also hereby incorporated by reference in its entirety. Such a juice extractor includes an upper drive housing and a juice extraction area below the drive housing. A series of drive rods extend through the bottom of the drive housing and to the extraction area. These drive rods typically pass through shaft seals carried by the drive housing. The drive shafts are moved reciprocally in an up and down fashion, but are also subject to transverse motion.
The components within the drive housing have been lubricated in the past with an oil bath. Accordingly, the shaft seals have also been lubricated with the oil bath. Newer generations of extractors, such as those disclosed in U.S. Pat. Publication No. 2006/0037498, for example, may now include grease as a lubricant for the components within the drive housing, and, thus, conventional shaft seals requiring oil lubricant may no longer be adequate. In addition, the juice extraction process may generate peel, frit, peel oil, and other debris in the juice extraction area that is desirably kept out of the drive housing.